function SubscribeNewsLetter() {
    var email = document.getElementById('txtEmailNewsLetter').value;
    
    if(!Common.IsEmail(email)) {
        alert(Lang.ControlsNewsletter_Email_NotValid);
    } else {
        Common.ShowOverlay('overlaySpinner', 110);
        Common.ShowSpinner();
        
        Json.Init();
        Json.Add("EMAIL", email);

        Json.SendToServer('/ajax/subscribenewsletter.aspx', 'doSubscribeNewsLetter', '', '');
    }
}